1. Field of the Invention
The present invention relates to a resectoscope apparatus which incises, resects, and transpires the body tissue through electric resection under an endoscope.
2. Description of the Related Art
Generally, a resectoscope is used for transurethral resection (TUR) and transcervical resection (TCR), and mainly comprises an optical scope (also referred to as a scope) as an endoscope for observation and an electrode unit for resecting the organ in an elongated and hollow sheath inserted in the celom.
The resectoscope apparatus includes two types of one for treatment in a non-conductive solution and one for treatment in a conductive solution.
Upon treatment such as the prostatectomy by using the resectoscope apparatus for treatment in the non-conductive solution, the space is expanded by supplying D-sorbitol as an insulative transparent solution corresponding to perfusate for expanding the narrow space and the sheath of the resectoscope is inserted into the space.
High-frequency current is energized to a treatment electrode of the electrode unit arranged to the opening of a distal end portion of the sheath while observing a surface of the lesion portion by using the resectoscope arranged in the sheath.
The high-frequency current flows to a counter-electrode plate as an external electrode arranged to the outside of the body via the body organ from the treatment electrode. An operator advances or retracts the treatment electrode by operating an operating unit for the treatment of the lesion portion.
In the case of the prostatectomy by using the resectoscope apparatus for treatment in the conductive solution, physiological saline or the like is used for the perfusate as the conductive solution. In the technology disclosed in Japanese Unexamined Patent Application Publication No. 2000-201946, a return electrode is arranged near the distal end portion of the elongated and hollow sheath inserted in the celom filled with a conductive solution and the high-frequency current from the treatment electrode is collected via the return electrode.